2016-09-20_REVISION - M2004031 ‎(4)‎

• Permit No: M2004031
• IBM Index Class Name: REVISION
• Doc Date: 9/20/2016
• From: Ioana Comaniciu, P.E.
• To: DRMS
• Type & Sequence: AM1
• Email Name: ECS
• Media Type: D
• Archive: No

ICOLORADO
Division of Water Resources
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1313 Sherman Street, Room 821
Denver, CO 80203
Response to Reclamation Permit Amendment Application Consideration
DATE: September 20, 2016
TO: Eric Scott, Environmental Protection Specialist
CC: Division 1 Office, District 2 Water Commissioner
FROM: loana Comaniciu, P.E.
RE: Hazeltine Mine, File No. M-2004-031(AM01)
Operator: Aggregate Industries-WCR, Inc.
Contact: Connie N. Davis, [phone]
Section 9, Twp 2 South, Rng 67 West, 6th P.M., Adams County
COMMENTS: Aggregate Industries-WCR, Inc. requested an amendment (AM01) to the application for
Hazeltine Mine, Permit no. M2004-031. The purpose of this amendment is to incorporate a permanent
ground water mounding mitigation plan into the final reclamation of the site. We have previously
provided comments to the amended application (AM01) by our letter dated January 13, 2016. On
September 1, 2016 the Applicant submitted a technical revision to the pending AM01 application in
order to address adequacy issues identified by the DRMS.
As mentioned in our previous letter, a soil-bentonite slurry wall keyed into the bedrock was
constructed around the perimeter of the Hazeltine Mine. The installation of the slurry wall caused
ground water mounding into an adjacent property, known as Orr property. In the amended AM01
application, the operator is proposing to construct a permanent drain to reduce ground water levels
from Orr property into the Hazeltine Mine Pit. The propose system will be a gravity system where
partial flows from the Bull Seep and groundwater seepage will be diverted through the mine and
from there conveyed back to Bull Seep and the South Platte River. Since our original review of the
AM01 application the Applicant obtained the liner approval of the Hazeltine Mine on May 25, 2016.
A Memo dated August 24, 2016 from Tetra Tech indicates that Aggregate Industries initially installed
a temporary Agridrain system that drain water flows directly into Hazeltine Mine from the Orr
property. Subsequently two temporary 18-inch pipes were place through the slurry wall at elevation
5038 feet to improve drainage. According to the Tetra Tech Memo the permanent drain system will
replace both the temporary Agridrain system and the temporary pipe system. The State Engineer's
Office is concerned that replacement of the temporary 18-inch pipes place through the slurry wall
will affect the previously approved liner for this reservoir. Therefore, the Applicant may be
required to perform a final leak test once replacement of the temporary pipes is complete. The
final leak test will be allowed to have a modified duration of 30-days as long as the liner continues to
satisfactorily operate during this time.
All water pumped from the drain shall not be used for any beneficial purposes and must be discharge
to the stream system without consumptive use. Water shall not be impounded in the reservoir except
pursuant to lawful diversions allowed by statute or decree. At all other times, all inflow of water into
the reservoir from any source, including precipitation, ground water inflows and drain water shall be
1313 Sherman Street, Room 821, Denver, CO 80203 P 303,866.3581 F 303.866.3585 www.water.state.co.us
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